Equine dental diseases Joan Howard ISU Equine Field Services.
Transcript of Equine dental diseases Joan Howard ISU Equine Field Services.
Equine dental diseases
Joan HowardISU Equine Field Services
Why do horses need regular and thorough dental care?
To prevent serious health problemsTo make eating and performing more comfortable for the horse
Dental Anatomy
Eruption of teeth
Horses have long permanent teeth which continue to erupt during the horse’s life time.
Width of mandible and maxilla
Maxilla is widerthan mandibleOutside of uppercheek teeth andinside of lower teeth become sharp
Types of dental disease
Congenital abnormalitiesEruption abnormalitiesDental trauma Disorders of wearPeriodontal diseaseTooth infections
Congenital abnormalities
Underbite Overbite
Eruption abnormalities
Variations from the normal pattern in which teeth penetrate thegums.
Eruption abnormalities: supernumerary teeth (extra teeth)
Last molar the most commonly affected
cheek toothIf tooth is unopposed maycause problems
Eruption abnormalities
Displaced eruptions
Eruption Abnormalities
Dentigerous cyst Dental tissue is located at sites away
from the jaw often found in the temporal area with
a sinus tract leading to the base of the opposite ear
Eruption abnormalities
Unerupted wolf teeth wolf teeth lay parallel to the maxilla instead of eruptingthrough the gum If not removed may cause resentment ofbit
Eruption abnormalities
Retained caps If caps are not shed may impact
permanent tooth If removed too early may stop cause
abnormal development of cheek teeth
Eruption abnormalities Eruption cysts
Pressure of cap on unerupted permanent tooth can cause cyst formation in the mandible
may become infected
Eruption abnormalities
Retained deciduous (baby teeth) incisors May be mistaken as supernumerary
teeth Along with overcrowding, common in
miniature horses
Dental trauma
May result from dental procedures
Often due toDirect trauma
Dental trauma
Failure to treat appropriately may cause serious malocclusions
X-rays may be needed to evaluate the supporting bone
Disorders of wear
chewing surface irregularities
interfere with horse’s ability to chew food
most common form of equine dental disease
Disorders of wearSharp enamel points cheek teeth erupt, wear and develop
sharp enamel edges sharp edges can cause cheek and
tongue ulcerations
Sharp enamel points
pain may change chewing patterns and cause abnormalities of wear
Maxillary cheek teeth beforeand after floating
Disorders of wear
Hooks tooth overgrowths which develop as a
result of incomplete chewing surface contact
First cheek teeth and last cheek teeth commonly develop hooks which may cause oral pain and interfere with chewing
Rostral hooks ofsecond premolar
Disorders of wear
Wave mouth an undulating appearance of the
cheek teeth
Disorders of wearStep mouth A rectangular or triangular over
growth opposite a missing or shorter opposing tooth
Disorders of wear
Abnormalities of incisors More common on high grain diets Four different types
Periodontal disease
Progressive inflammation of the supporting structures of the toothPockets around gum-line of teeth may form
Complications of periodontal disease
Feed and debris may become impacted in the periodontal pockets and causeinfection and loss of thetooth
Tooth infections
May be caused by trauma, abnormal wear, or periodontal diseaseMay cause nasal discharge, sinus infection, draining from jaw, or loss of the toothTooth often needs to be removed
Infected maxillary cheek tooth
Infundibular necrosis
irregularities may be packed with food and lead to bacterial fermentation dissolution of surrounding cementum,
dentin and enamel infection of the pulp chamber splitting or cracking of the tooth
during mastication
Dental tumors
Odontogenic tumors Ameloblastoma Ameloblastic odontomas Complex odontoma Compound odontoma Cementoma
performing the dental
Equipment Examination Floating and correcting abnormalities
Equipment:Tranquilization
Safer and easier to do a thorough examination and treatment
Equipment
Dental halter: needs a noseband that allows the
horse to open its mouth wide enough to perform dental procedures
Equipment
Mouth speculums: Gag: a wedge is placed between the
upper and lower molar arcades. Can cause trauma to the teeth
Equipment
Full mouth speculum More cumbersome Need chemical restraint Mouth shouldn’t be left open for more
than 30 minutes. Allows better visual and digital
inspection of oral cavity
McAllen style speculum
Mcpherson type
Stubb’s speculum
Equipment
Head support
Equipment
Dose syringe
Light source
The examination
Look at the whole animalHistory of medical
of behavioral problemsCurrent on tetanus
vaccination? Consider the possibility
of other systemic problems
Examination of the headNote symmetry and conformation of head.Check for swelling of mandible or maxillaNote if nasal or ocular
dischargeOpen mouth and percuss
frontal and maxillary sinuses.Note lymph nodes
Oral examination
Rinse mouth with dose syringe 4 min after tranquilization of horse Note if food
packed in cheeks
Exam with full mouth speculum
Make sure that incisors are well placed on speculumKeep free hand on the horse’s nose or on the speculum
Examination with full mouth speculum
Observe oral soft tissue (palate, tongue, buccal mucosa).
Exam with full mouth speculum
Teeth: look at conformation, position and number. Occlusal surface
mid arcade long teethwave mouth cupped out teeth decayed
infundibula missing or
damaged crowns
Treatment of Dental Disease
Equipment Routine dental careTreatment of dental disorders
Hand floats
Rotary tools
Air driven equipment
Power float
Floating the cheek teeth with hand tools
purpose of floating is: to remove sharp enamel points from
the buccal edges of the maxillary cheek teeth
lingual aspect of the mandibular cheek teeth
to round the rostral surfaces of 06’s to Remove hooks, and level the arcades to restore the normal 10-15 degree angle to
occlusal surfaces
Maxillary cheek teeth
Easier to use two hands. Left hand is on the shaft of the float to control direction and amount of pressure placed on float.Keep blade at about a 45 degree angle to buccal side of tooth.
Floating mandibular cheek teeth
Remove enamel points from lingual edges of mandibular cheek teeth. Use a straight or offset float. Use two hands
Bit seatsthe bit may cause
discomfort when it presses soft tissue in the mouth against the rostral surfaces of 06’s
To make a bit seat, the rostral aspects of 06’s are rounded
Bit SeatBit Seat
Wolf tooth extraction
Local analgesics can be used Burgess elevator and root elevator loosen tooth
Extraction of Wolf ToothExtraction of Wolf Tooth
Treatment: disorders of wear
Over-growths are removed and strive to return to normal occlusionIn older horses over-growths are just taken out of occlusion
Treatment: disorders of wear
Incisor wear abnormalities Avoid removing more than 2mm of
incisors in one session
With fractures of mandible or avulsed incisorsStabilization may prevent malocclusions
Treatment: dental trauma
Pulp capping Debride and stop bleeding Calcium hydroxide or dental resin
used to restore tooth Keep out of occlusion 3 months If periapical sepsis remove tooth
Treatment: periodontal disease
Prevention by regular prophylactic careCorrect abnormal wear Periodontal pockets irrigatedPockets enlarged if possible to discourage food packingIf tooth is diseased, endodontic procedures or extraction may be necessary
Treatment: eruption abnormalities
Removing deciduous incisors Radiographs if position of
deciduous or permanent teeth is questionable
Elevate alveolar attachments Remove with forceps
Treatment: eruption abnormalities
Eruption cysts Remove deciduous cap if present
(may need radiograph to identify) Antibiotics if septic If apical damage may require
extraction
Treatment: eruption abnormalities
Unerupted wolf teeth May use radiographs to identify Place burgess over mucosa of rostral
aspect of tooth Tooth is elevated from attachments
Treatment: eruption abnormalities
Retained deciduous teeth Removing deciduous premolars
Identify crease between deciduous and permanent tooth
Use forceps, extractors or screw driver
Clamp base of capRock cap lingually
Treatment: infundibular necrosis
Extraction of tooth if severeRestoration of defect
Remove food from defect
Round bur used to prepare area
Dental adhesive then composit resin applied in 2mm layers
Treatment: Apical root infections
Conservative therapy with antibiotics
Better prognosis with mandibular teeth
Use broad spectrum antibioticsMay be more successful in younger
animals
Treatment: apical root infections
Sinus involvement trephination and irrigation Surgical endodontics (apicoectomy,
root end resection)More successful in mandibular
cheek teethRoot of tooth must be mature Mixed results among practitioners
Surgical endodontics
Treatment: apical root infections
Tooth extraction Lateral buccotomy Repulsion
Punch and mallet used to drive toothfrom its socket
Can damage supporting boneBreaks up tooth into small pieces